Performing Case-Insensitive Searches in SQL

Using ILIKE in PostgreSQL and LIKE in MySQL/SQL Server

Write a SQL query to perform case-insensitive searches, using ILIKE in PostgreSQL and LIKE with LOWER() in MySQL/SQL Server.

Solution:

-- PostgreSQL
SELECT EmployeeID, Name
FROM Employees
WHERE Name ILIKE '%john%';

-- MySQL/SQL Server
SELECT EmployeeID, Name
FROM Employees
WHERE LOWER(Name) LIKE '%john%';

Explanation:

• Purpose of the Query :
• The goal is to demonstrate how case-insensitive searches differ between PostgreSQL and other databases.
• Key Components :
• ILIKE (PostgreSQL): Performs case-insensitive pattern matching.
• LOWER() with LIKE (MySQL/SQL Server): Converts text to lowercase for comparison.
• Why Compare Case-Insensitive Searches?:
• Case sensitivity varies across platforms, impacting query behavior.
• Understanding these differences ensures accurate results.
• Real-World Application :
• In search systems, case-insensitive searches improve user experience.

Additional Notes:

• Use ILIKE in PostgreSQL for simplicity and LOWER() in MySQL/SQL Server for compatibility.
• Test queries on all target platforms to ensure consistent results.
• Important Considerations:
• Avoid unnecessary use of LOWER() for performance reasons.

For more Practice: Solve these Related Problems:

• Write a SQL query to perform a case-insensitive search for product names, using ILIKE in PostgreSQL and LIKE with LOWER() in MySQL/SQL Server.
• Write a SQL query to perform a case-insensitive search for customer names, using ILIKE in PostgreSQL and LIKE with LOWER() in MySQL/SQL Server.
• Write a SQL query to perform a case-insensitive search for order IDs, using ILIKE in PostgreSQL and LIKE with LOWER() in MySQL/SQL Server.
• Write a SQL query to perform a case-insensitive search for employee names, using ILIKE in PostgreSQL and LIKE with LOWER() in MySQL/SQL Server.




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